Prior art automatic fastening machines are well known in the art and one such example is U.S. Pat. No. 4,515,302 issued May 7, 1985 which discloses a device for receiving, transferring and inserting a rivet into a hole in a workpiece. The foregoing machine utilizes rivet grasping fingers for holding a rivet and moving it into an inserted position in a hole drilled in the workpiece. It is also necessary to provide means for transferring each rivet in proper alignment to the rivet grasping fingers. The rivet grasping fingers are rigid and must be opened before the rivet can be finally assembled to the workpiece.
While the above prior art design and other similar prior art designs perform in a satisfactory manner, they have several disadvantages. Thus, it is not always possible to insert fasteners close to vertical obstructions, into close corners, and into deep holes or pockets. In addition, the grasping fingers cannot be easily and quickly replaced. Also, it may be necessary to replace the grasping fingers when fasteners of differing sizes are to be installed. Furthermore, when using slug fasteners, it is sometimes difficult to achieve proper orientation of the slug prior to insertion. In addition, it is necessary to utilize a precision mechanical injector for positioning the fasteners so that they can be grasped by the fingers.